Addressing the 5G cell switch-off problem with a multi-objective cellular genetic algorithm

© 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The power consumption foreseen for 5G networks is expected to be substantially greater than that of 4G systems, mainly because of the ultra-dense deployments required to meet the upcoming traffic demands. This paper deals with a multi- objective formulation of the Cell Switch-Off (CSO) problem, a well-known and effective approach to save energy in such dense scenarios, which is addressed with an accurate, yet rather unknown multi-objective metaheuristic called MOCell (multi- objective cellular genetic algorithm). It has been evaluated over a different set of networks of increasing densification levels. The results have shown that MOCell is able to reach major energy savings when compared to a widely used multi-objective algorithm.TIN2016-75097-P Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Phase Shifter for Millimeter-Wave Frequency Range Based on Glide Symmetric Structures

The use of glide symmetry in radiofrequency devices to introduce dispersive effects has been recently proposed and demonstrated. One of these effects is to control the propagation constant of the structure. Here, we propose a mm-wave phase shifter whose elements have a glide-symmetric configuration to achieve a greater phase shift in the same waveguide space than the non-glide-symmetric case. The glide-symmetric phase shifter is implemented in waveguide technology and is formed by rows of metallic pins that produce the desired phase shift. To assess the better performance of the glide-symmetric phase shifter, it is compared to its non-glide-symmetric version whose metallic pins are located only in one of the broad sides of the waveguide. The operating frequency range of the phase shifter is 67 to 75 GHz. Results show a 180 degree phase shift in regard to the reference waveguide without pins, and 50 degrees more than the non-glide-symmetric version.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Adiós a las plazas

Los parques son un patrimonio sentimental de los bumangueses, orgullosos de que la capital santandereana se haya ganado en el ámbito nacional el apelativo de “la ciudad de los parques”, convirtiéndose en un referente que hoy nos llama a la refexión. Su valor patrimonial no lo constituye ni el bronce ni el mármol que en ellos se erigen, ni su valor simbólico se reduce a la calidad del personaje que los representa. Cada uno contiene el signifcado de una época, las aspiraciones de una generación sobre el porvenir de una ciudad que se hacía con el trasegar de los años, después de medio siglo de guerras civiles y pobreza general

Inkjet printing digital image generation and compensation for surface chemistry effects

Additive manufacturing (AM) of electronic materials using digital inkjet printing (DIJP) is of research interests nowadays because of its potential benefits in the semiconductor industry. Current trends in manufacturing electronics feature DIJP as a key technology to enable the production of customised and microscale functional devices. However, the fabrication of microelectronic components at large scale demands fast printing of tight features with high dimensional accuracy on substrates with varied surface topography which push inkjet printing process to its limits. To understand the DIJP droplet deposition on such substrates, generally requires computational fluid dynamics modelling which is limited in its physics approximation of surface interactions. Otherwise, a kind of “trial and error” approach to determining how the ink spreads, coalesce and solidifies over the substrate is used, often a very time-consuming process. Consequently, this thesis aims to develop new modelling techniques to predict fast and accurately the surface morphology of inkjet-printed features, enabling the optimisation of DIJP control parameters and the compensation of images for better dimensional accuracy of printed electronics devices. This investigation explored three categories of modelling techniques to predict the surface morphology of inkjet-printed features: physics-based, data-driven and hybrid physics-based and data-driven. Two physics-based numerical models were developed to reproduce the inkjet printing droplet deposition and solidification processes using a lattice Boltzmann (LB) multiphase flow model and a finite element (FE) chemo-mechanical model, respectively. The LB model was limited to the simulation of single tracks and small square films and the FE model was mainly employed for the distortion prediction of multilayer objects. Alternatively, two data-driven models were implemented to reconstruct the surface morphology of single tracks and free-form films using images from experiments: image analysis (IA) and shape from shading (SFS). IA assumed volume conservation and minimal energy drop shape to reconstruct the surface while SFS resolved the height of the image using a reflection model. Finally, a hybrid physics-based and data-driven approach was generated which incorporates the uncertainty of droplet landing position and footprint, hydrostatic analytical models, empirical correlations derived from experiments, and relationships derived from physics-based models to predict fast and accurately any free-form layer pattern as a function of physical properties, printing parameters and wetting characteristics. Depending on the selection of the modelling technique to predict the deformed geometry, further considerations were required. For the purely physics-based and data-driven models, a surrogate model using response surface equations was employed to create a transfer function between printing parameters, substrate wetting characteristics and the resulting surface morphology. The development of a transfer function significantly decreased the computational time required by purely physics-based models and enabled the parameter optimisation using a multi-objective genetic algorithm approach to attain the best film dimensional accuracy. Additionally, for multilayer printing applications, a layer compensation approach was achieved utilizing a convolutional neural network trained by the predicted (deformed) geometry to reduce the out of plane error to target shape. The optimal combination of printing parameters and input image compensation helped with the generation of fine features that are traditionally difficult for inkjet, improved resolution of edges and corners by reducing the amount of overflow from material, accounted for varied topography and capillary effects thereof on the substrate surface and considered the effect of multiple layers built up on each other. This study revealed for the first time to the best of our knowledge the role of the droplet location and footprint diameter uncertainty in the stability and uniformity of printed features. Using a droplet overlap map which was proposed as a universal technique to assess the effect of printing parameters on pattern geometry, it was shown that reliable limits for break-up and bulging of printed features were obtained. Considering droplet position and diameter size uncertainties, predicted optimal printing parameters improved the quality of printed films on substrates with different wettability. Finally, a stability diagram illustrating the onset of bulging and separation for lines and films as well as the optimal drop spacing, printing frequency and stand-off distance was generated to inform visually the results. This investigation has developed a predictive physics-based model of the surface morphology of DIJP features on heterogeneous substrates and a methodology to find the printing parameters and compensate the layer geometry required for optimum part dimensional accuracy. The simplicity of the proposed technique makes it a promising tool for model driven inkjet printing process optimization, including real time process control and paves the way for better quality devices in the printed electronics industry

Turismo en República Dominicana y España

Facultad de Ciencias de la EmpresaUniversidad Politécnica de Cartagen

Compositos moleculares de soluciones sólidas poliméricas

Fundamentado en los antecedentes de formación de soluciones sólidas de sales inorgánicas en polímeros, se planteó la posibilidad de que el 2,2- dimetoxipropano actuara como agente de secado cuando las soluciones se preparan ya sea en medios húmedos o a partir de sales hidratadas, así se estableció un diseño de experimentos para determinar si era posible tener tiempos cortos de preparación de las muestras, para tal efecto se seleccionaron cinco sales hexahidratadas (FeCl3, CoCl2, Co(NO3)2, Zn(NO3)2, Sm(NO3)3) para ser formuladas en composiciones cercanas al 50% en poli (propilenglicol). Los materiales compuestos fueron preparados con tiempos de secado de 48 Hrs. y su composición fue caracterizada mediante termogravimetría y espectroscopia de infrarrojo. Además utilizando calorimetría diferencial de barrido, difracción de rayos–X y espectroscopia de ultravioleta – visible, se estableció la característica de soluciones sólidas, que incluyó un posible orden de intensidad de las interacciones entre las sales y el polímero. Por último la espectroscopia dieléctrica preliminar de disoluciones de los materiales en etanol, mostró diferencias en el comportamiento entre las diversas soluciones sólidas cuya correcta interpretación requiere de un trabajo experimental caracterizando los materiales en estado sólido. De esta manera se estableció que el 2,2- dimetoxipropano actúa como agente de secado en la preparación de disoluciones sólidas de las sales estudiadas en poli (propilenglicol), reduciendo los tiempos de preparación de los materiales, de alrededor de tres semanas, que es lo reportado, a 48 Hrs. que es lo reportado en este trabajo

VIE Project: Cultural values and socioeconomic factors as determinants of entrepreneurial intentions

This paper describes a research project currently being developed by the authors. It aims to analyse the role played by psychosocial, cultural and socioeconomic factors in shaping the entrepreneurial intention. Survey methods will be used on a population of potential entrepreneurs (having not yet performed actual entrepreneurial behaviours). In this sense, undergraduate students and individuals contacting business support centres will be considered as part of the sample. We expect to get a clearer understanding of the psychosocial elements, socioeconomic factors and cultural values affecting the venture-creation decision. The results would be important to policy makers (showing them what to encourage), to practitioners (what to do better), and to researchers (what to clarify)

Publication venue recommendation using profiles based on clustering

This work was supported by the Spanish “Agencia Estatal de Investigación” [grant number PID2019-106758GB-C31/AEI/10.13039/501100011033]; the Span- ish “Programa operativo FEDER Andalucı́a 2014-2020 de la Junta de Andalucı́a y la Universidad de Granada” [grant number A-TIC-146-UGR20]; and the Eu- ropean Regional Development Fund (ERDF-FEDER).In this paper we study the venue recommendation problem in order to help researchers to identify a journal or conference to submit a given paper. A com- mon approach to tackle this problem is to build profiles defining the scope of each venue. Then, these profiles are compared against the target paper. In our approach we will study how clustering techniques can be used to construct topic-based profiles and use an Information Retrieval based approach to obtain the final recommendations. Additionally, we will explore how the use of author- ship, representing a complementary piece of information, helps to improve the recommendations

Committee-Based Profiles for Politician Finding

One step towards breaking down barriers between citizens and politicians is to help people identify those politicians who share their concerns. This paper is set in the field of expert finding and is based on the automatic construction of politicians’ profiles from their speeches on parliamentary committees. These committee-based profiles are treated as documents and are indexed by an information retrieval system. Given a query representing a citizen’s concern, a profile ranking is then obtained. In the final step, the different results for each candidate are combined in order to obtain the final politician ranking. We explore the use of classic combination strategies for this purpose and present a new approach that improves state-of-the-art performance and which is more stable under different conditions. We also introduce a two-stage model where the identification of a broader concept (such as the committee) is used to improve the final politician ranking.This work has been funded by the Spanish Ministerio de Economı́a y Competitividad under projects TIN2013-42741-P and TIN2016-77902-C3-2-P, and the European Regional Development Fund (ERDF-FEDER)

An explainable content-based approach for recommender systems: a case study in journal recommendation for paper submission

Funding for open access publishing: Universidad de Granada/CBUA. This work was jointly funded by MCIN/ AEI /10.13039/501100011033 under project PID2019-106758GB-C31 and the Spanish “FEDER/Junta de Andalucía-Consejería de Transformación Económica, Industria, Conocimiento y Universidades” under Grant A-TIC-146-UGR20, and the European Regional Development Fund (ERDF - FEDER Una manera de hacer Europa). The State Research Agency (SRA) and European Regional Development Fund (ERDF) under project PID2022-139293NB-C33.Explainable artificial intelligence is becoming increasingly important in new artificial intelligence developments since it enables users to understand and consequently trust system output. In the field of recommender systems, explanation is necessary not only for such understanding and trust but also because if users understand why the system is making certain suggestions, they are more likely to consume the recommended product. This paper proposes a novel approach for explaining content-based recommender systems by specifically focusing on publication venue recommendation. In this problem, the authors of a new research paper receive recommendations about possible journals (or other publication venues) to which they could submit their article based on content similarity, while the recommender system simultaneously explains its decisions. The proposed explanation ecosystem is based on various elements that support the explanation (topics, related articles, relevant terms, etc.) and is fully integrated with the underlying recommendation model. The proposed method is evaluated through a user study in the biomedical field, where transparency, satisfaction, trust, and scrutability are assessed. The obtained results suggest that the proposed approach is effective and useful for explaining the output of the recommender system to users.Universidad de Granada/CBUAMCIN/ AEI /10.13039/501100011033 PID2019-106758GB-C31, PID2022-139293NB-C33FEDER/Junta de Andalucía A-TIC-146-UGR20European Regional Development Fun